NDA Biology · Human Physiology
Nutrition, Vitamins and Minerals
A balanced diet supplies seven components; vitamins and minerals are the micronutrients whose deficiency causes specific named diseases.
Why this matters
8 PYQs, and the vitamin-deficiency table is the single highest-yield recall block in the whole chapter — it recurs almost every year. Learn each vitamin's chemical name, its deficiency disease, and its source; the bank tests all three angles and sneaks in non-deficiency diseases (rabies, hepatitis) as traps.
Concept 1 of 3: Vitamins — chemical name, deficiency, and source
Vitamins are micronutrients the body cannot make in sufficient amounts. Each has a letter, a chemical name, a deficiency disease, and a food source — and the NDA can ask from any of those four columns. The reliable trap is mixing an infectious disease (rabies, hepatitis) into the options, because those are NOT deficiency diseases.
Definition
The high-yield vitamin facts:
- B1 (Thiamin) — deficiency: beriberi.
- B2 (Riboflavin), B12 (Cobalamin) — B12 is uniquely made by intestinal bacteria and found in animal foods.
- C (Ascorbic acid) — deficiency: scurvy (bleeding gums); source: citrus fruits.
- D (Calciferol) — deficiency: rickets (bone deformity); source: sunlight.
- K (Phylloquinone) — needed for blood clotting; source: leafy greens + gut bacteria.
- A (Retinol) — deficiency: night blindness. E (Tocopherol) — antioxidant.
| Vitamin | Chemical name | Deficiency disease | Source |
|---|---|---|---|
| A | Retinol | Night blindness | Carrots, liver |
| B1 | Thiamin | Beriberi | Whole grains |
| B12 | Cobalamin | Anaemia | Intestinal bacteria, animal foods |
| C | Ascorbic acid | Scurvy | Citrus fruits NDA 2019 — Vitamin C deficiency = scurvy (NOT rickets, which is Vitamin D). |
| D | Calciferol | Rickets | Sunlight |
| K | Phylloquinone | Poor blood clotting | Leafy greens, gut bacteria |
Deficiency diseases only. Rabies and hepatitis are INFECTIOUS — never the answer to a deficiency question.
Practice this conceptself-check · 5 quick reps
The same idea in a real exam question:
NDA · Sep 2019 · Q95Easy
Example 1 · Human Physiology · Nutrition, Vitamins and Minerals
Which one of the following diseases may be caused by the deficiency of vitamin C?
Not every disease in the options is a deficiency disease
A deficiency question may list rabies or hepatitis among the options — both are infections, not nutrient deficiencies. Rickets (D), scurvy (C) and beriberi (B1) are the deficiency answers.
Don't confuse the chemical names
Thiamin = B1, Riboflavin = B2, Retinol = A, Tocopherol = E. The bank lines all four up as options for 'B1 is also known as ___'; the answer is Thiamin.
Concept 2 of 3: Balanced diet and macronutrients
A balanced diet is not just 'food' — it is a specific list of seven components the body needs in the right proportions. Alongside it, the NDA tests basic biomolecule facts: all enzymes are proteins, but not all proteins are enzymes.
Definition
The components and the biomolecule facts the bank tests:
- A balanced diet has seven components: carbohydrates, proteins, fats, vitamins, minerals, fibre (roughage), and water.
- Carbohydrates (e.g. glucose) and fats are energy-rich; fats give the most energy per gram.
- Proteins build and repair. All enzymes are proteins, but not all proteins are enzymes — many are structural (collagen, keratin) or transport (haemoglobin).
- Fruits and vegetables are the richest source of vitamins and minerals.
| Component | Main role |
|---|---|
| Carbohydrates | Main energy source (glucose) |
| Proteins | Growth and repair |
| Fats | Energy store (most energy per gram) |
| Vitamins + Minerals | Micronutrients (from fruits and vegetables) |
| Fibre (roughage) | Aids bowel movement |
| Water | Medium for all reactions |
Seven components — the bank's correct option lists all of them including fibre and water.
Practice this conceptself-check · 3 quick reps
The same idea in a real exam question:
NDA · Sep 2024 · Q85Easy
Example 2 · Human Physiology · Nutrition, Vitamins and Minerals
Which one among the following combinations most appropriately represent the components of balanced diet ?
Fibre and water count as diet components
The 'most complete' option for a balanced diet includes fibre (roughage) and water alongside carbs, proteins, fats, vitamins and minerals. Options dropping fibre or water are incomplete.
Concept 3 of 3: Minerals and metabolic waste
Minerals are inorganic micronutrients with very specific jobs — iodine for thyroxine, iron for haemoglobin, calcium for bone. The bank also asks one metabolism question: gout comes from too much uric acid, which is a breakdown product of the nucleic acids in food.
Definition
Key mineral facts plus the gout question:
- Iodine — needed by the thyroid to make thyroxine; deficiency causes goitre.
- Iron — needed for haemoglobin; deficiency causes anaemia.
- Calcium — bones, teeth, and blood clotting.
- Gout — caused by high uric acid, the breakdown product of purines in nucleic acids; gout patients should reduce nucleic-acid-rich foods.
| Mineral / waste | Linked to |
|---|---|
| Iodine | Thyroxine synthesis (deficiency → goitre) |
| Iron | Haemoglobin (deficiency → anaemia) |
| Calcium | Bones, teeth, clotting |
| Uric acid | From nucleic acids → high levels cause gout NDA 2017 — gout patients should minimise NUCLEIC-ACID-rich foods (uric acid comes from purines). |
Practice this concept3 quick reps
The same idea in a real exam question:
NDA · Sep 2017 · Q66Moderate
Example 3 · Human Physiology · Nutrition, Vitamins and Minerals
Intake of which one of the following food components should be minimized by patients having Gouty Arthritis due to elevated serum uric acid level?
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Reference tables (3)
Vitamins — chemical name, deficiency, and source6 rows
| Vitamin | Chemical name | Deficiency disease | Source |
|---|---|---|---|
| A | Retinol | Night blindness | Carrots, liver |
| B1 | Thiamin | Beriberi | Whole grains |
| B12 | Cobalamin | Anaemia | Intestinal bacteria, animal foods |
| C | Ascorbic acid | Scurvy | Citrus fruits NDA 2019 — Vitamin C deficiency = scurvy (NOT rickets, which is Vitamin D). |
| D | Calciferol | Rickets | Sunlight |
| K | Phylloquinone | Poor blood clotting | Leafy greens, gut bacteria |
Deficiency diseases only. Rabies and hepatitis are INFECTIOUS — never the answer to a deficiency question.
Balanced diet and macronutrients6 rows
| Component | Main role |
|---|---|
| Carbohydrates | Main energy source (glucose) |
| Proteins | Growth and repair |
| Fats | Energy store (most energy per gram) |
| Vitamins + Minerals | Micronutrients (from fruits and vegetables) |
| Fibre (roughage) | Aids bowel movement |
| Water | Medium for all reactions |
Seven components — the bank's correct option lists all of them including fibre and water.
Minerals and metabolic waste4 rows
| Mineral / waste | Linked to |
|---|---|
| Iodine | Thyroxine synthesis (deficiency → goitre) |
| Iron | Haemoglobin (deficiency → anaemia) |
| Calcium | Bones, teeth, clotting |
| Uric acid | From nucleic acids → high levels cause gout NDA 2017 — gout patients should minimise NUCLEIC-ACID-rich foods (uric acid comes from purines). |
Watch out for (3)
- Not every disease in the options is a deficiency disease→ Vitamins — chemical name, deficiency, and source
- Don't confuse the chemical names→ Vitamins — chemical name, deficiency, and source
- Fibre and water count as diet components→ Balanced diet and macronutrients
Test yourself on Human Physiology
15 past NDA questions from this chapter, timed at 15 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.